/*
Copyright 2022-2024 The Matrix.org Foundation C.I.C.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

import type { EmittedEvents, Preset } from "matrix-js-sdk/src/matrix";
import { expect, test } from "../../element-web-test";
import {
    createRoom,
    enableKeyBackup,
    logIntoElement,
    logOutOfElement,
    sendMessageInCurrentRoom,
    verifySession,
} from "./utils";
import { isDendrite } from "../../plugins/homeserver/dendrite";

test.describe("Cryptography", function () {
    test.use({
        displayName: "Alice",
        botCreateOpts: {
            displayName: "Bob",
            autoAcceptInvites: false,
        },
    });

    test.describe("decryption failure messages", () => {
        test("should handle device-relative historical messages", async ({
            homeserver,
            page,
            app,
            credentials,
            user,
        }) => {
            test.setTimeout(60000);

            // Start with a logged-in session, without key backup, and send a message.
            await createRoom(page, "Test room", true);
            await sendMessageInCurrentRoom(page, "test test");

            // Log out, discarding the key for the sent message.
            await logOutOfElement(page, true);

            // Log in again, and see how the message looks.
            await logIntoElement(page, homeserver, credentials);
            await app.viewRoomByName("Test room");
            const lastTile = page.locator(".mx_EventTile").last();
            await expect(lastTile).toContainText("Historical messages are not available on this device");
            await expect(lastTile.locator(".mx_EventTile_e2eIcon_decryption_failure")).toBeVisible();

            // Now, we set up key backup, and then send another message.
            const secretStorageKey = await enableKeyBackup(app);
            await app.viewRoomByName("Test room");
            await sendMessageInCurrentRoom(page, "test2 test2");

            // Workaround for https://github.com/element-hq/element-web/issues/27267. It can take up to 10 seconds for
            // the key to be backed up.
            await page.waitForTimeout(10000);

            // Finally, log out again, and back in, skipping verification for now, and see what we see.
            await logOutOfElement(page);
            await logIntoElement(page, homeserver, credentials);
            await page.locator(".mx_AuthPage").getByRole("button", { name: "Skip verification for now" }).click();
            await page.locator(".mx_AuthPage").getByRole("button", { name: "I'll verify later" }).click();
            await app.viewRoomByName("Test room");

            // There should be two historical events in the timeline
            const tiles = await page.locator(".mx_EventTile").all();
            expect(tiles.length).toBeGreaterThanOrEqual(2);
            // look at the last two tiles only
            for (const tile of tiles.slice(-2)) {
                await expect(tile).toContainText("You need to verify this device for access to historical messages");
                await expect(tile.locator(".mx_EventTile_e2eIcon_decryption_failure")).toBeVisible();
            }

            // Now verify our device (setting up key backup), and check what happens
            await verifySession(app, secretStorageKey);
            const tilesAfterVerify = (await page.locator(".mx_EventTile").all()).slice(-2);

            // The first message still cannot be decrypted, because it was never backed up. It's now a regular UTD though.
            await expect(tilesAfterVerify[0]).toContainText("Unable to decrypt message");
            await expect(tilesAfterVerify[0].locator(".mx_EventTile_e2eIcon_decryption_failure")).toBeVisible();

            // The second message should now be decrypted, with a grey shield
            await expect(tilesAfterVerify[1]).toContainText("test2 test2");
            await expect(tilesAfterVerify[1].locator(".mx_EventTile_e2eIcon_normal")).toBeVisible();
        });

        test.describe("non-joined historical messages", () => {
            test.skip(isDendrite, "does not yet support membership on events");

            test("should display undecryptable non-joined historical messages with a different message", async ({
                homeserver,
                page,
                app,
                credentials: aliceCredentials,
                user: alice,
                bot: bob,
            }) => {
                // Bob creates an encrypted room and sends a message to it. He then invites Alice
                const roomId = await bob.evaluate(
                    async (client, { alice }) => {
                        const encryptionStatePromise = new Promise<void>((resolve) => {
                            client.on("RoomState.events" as EmittedEvents, (event, _state, _lastStateEvent) => {
                                if (event.getType() === "m.room.encryption") {
                                    resolve();
                                }
                            });
                        });

                        const { room_id: roomId } = await client.createRoom({
                            initial_state: [
                                {
                                    type: "m.room.encryption",
                                    content: {
                                        algorithm: "m.megolm.v1.aes-sha2",
                                    },
                                },
                            ],
                            name: "Test room",
                            preset: "private_chat" as Preset,
                        });

                        // wait for m.room.encryption event, so that when we send a
                        // message, it will be encrypted
                        await encryptionStatePromise;

                        await client.sendTextMessage(roomId, "This should be undecryptable");

                        await client.invite(roomId, alice.userId);

                        return roomId;
                    },
                    { alice },
                );

                // Alice accepts the invite
                await expect(
                    page.getByRole("group", { name: "Invites" }).locator(".mx_RoomSublist_tiles").getByRole("treeitem"),
                ).toHaveCount(1);
                await page.getByRole("treeitem", { name: "Test room" }).click();
                await page.locator(".mx_RoomView").getByRole("button", { name: "Accept" }).click();

                // Bob sends an encrypted event and an undecryptable event
                await bob.evaluate(
                    async (client, { roomId }) => {
                        await client.sendTextMessage(roomId, "This should be decryptable");
                        await client.sendEvent(
                            roomId,
                            "m.room.encrypted" as any,
                            {
                                algorithm: "m.megolm.v1.aes-sha2",
                                ciphertext: "this+message+will+be+undecryptable",
                                device_id: client.getDeviceId()!,
                                sender_key: (await client.getCrypto()!.getOwnDeviceKeys()).ed25519,
                                session_id: "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa",
                            } as any,
                        );
                    },
                    { roomId },
                );

                // We wait for the event tiles that we expect from the messages that
                // Bob sent, in sequence.
                await expect(
                    page.locator(`.mx_EventTile`).getByText("You don't have access to this message"),
                ).toBeVisible();
                await expect(page.locator(`.mx_EventTile`).getByText("This should be decryptable")).toBeVisible();
                await expect(page.locator(`.mx_EventTile`).getByText("Unable to decrypt message")).toBeVisible();

                // And then we ensure that they are where we expect them to be
                // Alice should see these event tiles:
                // - first message sent by Bob (undecryptable)
                // - Bob invited Alice
                // - Alice joined the room
                // - second message sent by Bob (decryptable)
                // - third message sent by Bob (undecryptable)
                const tiles = await page.locator(".mx_EventTile").all();
                expect(tiles.length).toBeGreaterThanOrEqual(5);

                // The first message from Bob was sent before Alice was in the room, so should
                // be different from the standard UTD message
                await expect(tiles[tiles.length - 5]).toContainText("You don't have access to this message");
                await expect(tiles[tiles.length - 5].locator(".mx_EventTile_e2eIcon_decryption_failure")).toBeVisible();

                // The second message from Bob should be decryptable
                await expect(tiles[tiles.length - 2]).toContainText("This should be decryptable");
                // this tile won't have an e2e icon since we got the key from the sender

                // The third message from Bob is undecryptable, but was sent while Alice was
                // in the room and is expected to be decryptable, so this should have the
                // standard UTD message
                await expect(tiles[tiles.length - 1]).toContainText("Unable to decrypt message");
                await expect(tiles[tiles.length - 1].locator(".mx_EventTile_e2eIcon_decryption_failure")).toBeVisible();
            });

            test("should be able to jump to a message sent before our last join event", async ({
                homeserver,
                page,
                app,
                credentials: aliceCredentials,
                user: alice,
                bot: bob,
            }) => {
                // Bob:
                // - creates an encrypted room,
                // - invites Alice,
                // - sends a message to it,
                // - kicks Alice,
                // - sends a bunch more events
                // - invites Alice again
                // In this way, there will be an event that Alice can decrypt,
                // followed by a bunch of undecryptable events which Alice shouldn't
                // expect to be able to decrypt.  The old code would have hidden all
                // the events, even the decryptable event (which it wouldn't have
                // even tried to fetch, if it was far enough back).
                const { roomId, eventId } = await bob.evaluate(
                    async (client, { alice }) => {
                        const { room_id: roomId } = await client.createRoom({
                            initial_state: [
                                {
                                    type: "m.room.encryption",
                                    content: {
                                        algorithm: "m.megolm.v1.aes-sha2",
                                    },
                                },
                            ],
                            name: "Test room",
                            preset: "private_chat" as Preset,
                        });

                        // invite Alice
                        const inviteAlicePromise = new Promise<void>((resolve) => {
                            client.on("RoomMember.membership" as EmittedEvents, (_event, member, _oldMembership?) => {
                                if (member.userId === alice.userId && member.membership === "invite") {
                                    resolve();
                                }
                            });
                        });
                        await client.invite(roomId, alice.userId);
                        // wait for the invite to come back so that we encrypt to Alice
                        await inviteAlicePromise;

                        // send a message that Alice should be able to decrypt
                        const { event_id: eventId } = await client.sendTextMessage(
                            roomId,
                            "This should be decryptable",
                        );

                        // kick Alice
                        const kickAlicePromise = new Promise<void>((resolve) => {
                            client.on("RoomMember.membership" as EmittedEvents, (_event, member, _oldMembership?) => {
                                if (member.userId === alice.userId && member.membership === "leave") {
                                    resolve();
                                }
                            });
                        });
                        await client.kick(roomId, alice.userId);
                        await kickAlicePromise;

                        // send a bunch of messages that Alice won't be able to decrypt
                        for (let i = 0; i < 20; i++) {
                            await client.sendTextMessage(roomId, `${i}`);
                        }

                        // invite Alice again
                        await client.invite(roomId, alice.userId);

                        return { roomId, eventId };
                    },
                    { alice },
                );

                // Alice accepts the invite
                await expect(
                    page.getByRole("group", { name: "Invites" }).locator(".mx_RoomSublist_tiles").getByRole("treeitem"),
                ).toHaveCount(1);
                await page.getByRole("treeitem", { name: "Test room" }).click();
                await page.locator(".mx_RoomView").getByRole("button", { name: "Accept" }).click();

                // wait until we're joined and see the timeline
                await expect(page.locator(`.mx_EventTile`).getByText("Alice joined the room")).toBeVisible();

                // we should be able to jump to the decryptable message that Bob sent
                await page.goto(`#/room/${roomId}/${eventId}`);

                await expect(page.locator(`.mx_EventTile`).getByText("This should be decryptable")).toBeVisible();
            });
        });
    });
});
